An aerosol sprayer has been known which comprises a can-like aerosol container accommodating its content such as a chemical in its inside and a trigger type head cap fitted on the aerosol container.
The aerosol container accommodating its content such as a chemical in its inside is filled with a gas sealed up therein, and accommodates such contents as the chemical, being internally pressurized with the gas. And, it is equipped on its top with a stem normally biased upwards, which when pushed down allows the contents of the aerosol container to be sprayed out under the internal pressure.
On the other hand, the trigger type head cap has a cap cover fitted on the aerosol container and the cap cover has a tubular member formed with a stem mating part mating with the stem on the aerosol container, the tubular member ending with a jet orifice to form a flow path continuous from the stem mating part to the jet orifice in the tubular member. The head cap further has a trigger lever member capable of thrusting down the stem mating part of the tubular member in the cap cover.
In such makeup, pulling a trigger part of the trigger lever member causes the tubular member and its stem mating part to be thrust down. This causes the stem to be thrust down on the aerosol container, allowing the content of the aerosol container in its inside to spurt out of the stem, to pass through the flow path in the tubular member in the trigger type head cap and to be sprayed out of the jet orifice.
In such an aerosol sprayer, when an entire content accommodated inside of the aerosol container has been sprayed and used up (at an end of the use of an aerosol container), there is often the case that gas remains in the aerosol container, so that the container when disposed as a waste may have a danger of explosion accident due to the gas remaining in the container, that is the residual gas.
In order to get rid of such an explosion accident due to the residual gas, there is, for example, an aerosol sprayer what is described in JP 2006-44705 A. This has a generally cylindrical slide stopper adapted to slide back and forth on the tubular member in a region of the end of the tubular member such that when the trigger lever member is operated for spraying, the slide stopper is caused to slide forth to enter a gap formed between the trigger lever member and the tubular member and to fit in the gap whereby the trigger lever member is locked coming to hold the spraying state and thereby to discharge and eliminate the residual gas in the aerosol container.
In such an aerosol sprayer in the prior art in which to discharge and eliminate a residual gas in an aerosol container a slide stopper adapted to slide on a tubular member which is used when a trigger lever member is operated, is caused to slide forward and to enter a gap formed between the trigger lever member and the tubular member and fit in the gap, there is the possibility that the slide stopper when acted to fit in may hit against the trigger lever member and fail to fit in the gap snugly, unless the trigger lever member is acted correctly and yet hard to make the gap between the trigger lever and the tubular member left large. It is difficult to understand the operating method and very complicated to act on. Moreover, where in working to fit the slide stopper in, it is slid forwards it must then be much forced to slide. It is, here again, complicated to act on.
In light of such problems as complicacy in working to discharge and eliminate a residual gas in an aerosol container, it is an object of the present invention to provide a trigger type head cap for an aerosol sprayer, which can be worked easily and reliably.